which thermostat to use 143 degree or 160 degree in PCM ford 351w

Hi All,
Pleasure craft marine states on older ford 351 4bbl engines to use 143 degree thermostat with raw water cooling pump due to salt water crystals building up in the cooling system-- however for fresh water lakes you can use 160 degree thermostat-- better performance and fuel economy--We will use the boat about 90 hours a season in warm water 75 to 85 degrees with only about 3 trips to fish in the gulf of Mexico-- total 2 days fishing with boat at marina- engine running hours in salt water 16 hours each time then flush engine with fresh water -- which thermostat to use- 143 degree or 160 degree? and the thermostat is a #r002002e t-stat- which side goes up ?the side with the point facing up? or down?
thanks,
tmcboat

If you will be spending time between Ocean Water and River/Lake water, you had best stay with the 143* thermostat. This will help avoid salt crystallization.

Thermostats always intall with sensor side facing the engine.... or facing the outflowing coolant.
They must first sense the coolant (salt/river/lake water) temperature, or they will not function correctly.


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